Disco-Scopie v2.0 - SCP to extended ADF ?
 

Hi,

I have recently dumped the original floppy disk of a french utility called Disco-Scopie v2.0 by ESAT Software. I have bought it in 1990 or 1991.
Attachment 70930


This floppy seems to be standard AmigaOS format howerver there is probably a copy protection : dumping to regular ADF results in a non working floppy image. The loading stops on AmigaOS screen after displaying a date/time... and this title screen never displays :
Attachment 70929

I had to dump it to SCP file format with my new greaseweazle. This SCP file works unreliably under WinUAE (A500 standard config) :
Attachment 70928

I saw dlfrsilver has uploaded Disco-Scopie v3.0 to the FTP :
DiscoScopie (F) (Utilitaire Disquette) (1989) [Original v3.0] (Esat Software) (Amiga OCS 512ko) (MFM).zip
Interestingly, this v3.0 dump is an extended ADF format and works fine under WinUAE.

I have already tried to dump my original Disco-Scopie v2.0 floppy directly on my amiga to extended ADF with "rawread -r" and TSGui "Custom" mode => does not work or bypass protection.
I tried to convert the SCP file to extended adf with Keir Fraser's disk-analyse => does not bypass protection.


So I am wondering how can I convert my SCP file to a proper extended ADF, hopefully bypassing the protection ?
I uploaded the SCP file to The Zone.

Any clue I should investigate to achieve that ? http://eab.abime.net/images/smilies/confused.gif


I would like to submit it to Tosec, in the sake of preservation.

Do something simple : you have a greasleweasle ? Please dump your disk as kryoflux raw dump :

gw read Disk\track.raw --revs=5 --tracks=c=0-83

(Create before that the 'Disk' folder).

Then send me the resulting dump, i will do an IPF, and will make an extended ADF at the same time :)

I made a check : the protection is on track 80. Problem: your image doesn't contain anything on this track (checked with Aufit, track is seen as noise or unused).

kryoflux raw dump in the zone ;)

I was curious and opened the kryoflux raw dump I made earlier with Aufit and looked at the 80.0 tack. It looked like noise to my eyes but I have not the knowledge needed ;)

I added 2 more kryoflux raw dumps of this floppy to the Zone.
I have just made them with 2 different HD PC drives connected to my greaseweazle.

I have seen 3 nice peaks on Aufit histogram on the 80.0 track of "Dump_with_old_PC_drive_Mitsumi_1"... don't know if it's relevant. The dump produced by the other drives doesn't have those peaks.
Attachment 70933


I noticed an odd thing about my fist SCP dump : it works fine under WinUAE when floppy drive speed is set to 800% but does not work reliably when floppy drive set to "100% (compatible)" : it crashes with a blinking "Erreur fatale".

Zoned an unofficial IPF of Disco-Scopie.

Works fine under emulation.

Also writes back to disk using older drives (tested TEAC FD-235F and FD-235HF). Newer drives (tested NEC FD1231M) do not like the long 16us flux times which form part of the key pattern on track 160.

thanks Keir :)

Thank you very much Keir ! :great

After pulling your latest disk-analyse commit, I even managed to convert this IPF to an extended ADF that also works reliably under WinUAE.

I got a TEAC FD-235F and will try later on the writing process.

Hello
old messages ; As the author of Discoscopie, I can tell you that the original track 80 was protected with the "long track" method, which consists to write data with a rotation speed lower than the regular one. You can write overdata as long track and cannot be copied with a normal floppy disk device. The data can be completely read out with a standard floppy reader (because of the raw MFM sync) and you can check the data length to ensure that this is the original disk.

Mr Frédéric Sol, welcome aboard :)

As pointed, a longtrack use normally bitcell in 2us. Here Keir discovered it was not the case (16us).

I use a custom tool to encode flux/stream dumps, and the protection is not seen or recognized at 2us.

@gizyfr : welcome and thanks for this piece of information !

@dlfrsilver : At what stage is the project to include "unofficial" IPFs in the TOSEC ?
It would be great to preserve software like DiscoScopie. I have archived the IPF image made by Keir.
IPF is the most elegant way, isn't it ?

Yes it is :) Small file and easy to write :)

This will be done for the next release :great

Yes ! Thank you !

Merci for that Crashdisk !

It's my turn to thank you!
Also note that a non-SPS IPF games section is currently in progress :-)

Good :)

I am glad too see Disco-Scopie v2 is the first IPF included in "Commodore Amiga - Applications - [Unofficial IPF]" brand new Tosec DAT !

;)

That's incredibly cool ! :D

Dump your apps! Let's get them all :D

And well done to Jami for breaking the ice :)